This invention relates generally to a matrix type liquid crystal display driving system and more particularly to an active matrix type liquid crystal display driven with a generalized AC amplitude selective multiplexed driving signal. Conventionally, there are three methods for driving a liquid crystal. First, a generalized AC amplitude selective multiplexing driving method is utilized. Secondly, in an active matrix device, a switching transistor is introduced in series with the liquid crystal. Thirdly, in an active matrix apparatus, diodes which have different directional properties are introduced separately and in series with the liquid crystal with the directional properties of the diodes opposed.
However, each of these concepts has its problems. The first concept using the multiplex drive is limited because of the liquid crystal characteristics and it is difficult to actually produce a display having high resolution. In the second concept the transistor switch is formed by a MOS integrated circuit or TFT. The production process has many steps and conditions must be rigidly controlled during production. Therefore, it is difficult with regard to cost to produce a large frame for display using liquid crystals. Regarding the third concept, scanning electrodes are needed in the positive and the negative directions respectively separate. Therefore, the wiring within the panel and the peripheral circuitry is very complicated.
What is needed is an active matrix type liquid crystal display apparatus which has simple circuitry and provides a high contrast, high resolution display.